Induced mutation breeding for qualitative and quantitative traits and varietal development in medicinal and aromatic crops at CSIR-CIMAP, Lucknow (India): past and recent accomplishment.

PURPOSE: The nature and kind of some successful mutations achieved through gamma radiation at CSIR-CIMAP, Lucknow are reviewed and described in this article. Medicinal and aromatic crops (MACs) came under the mutation-breeding program very late - perhaps during the 1980s in India. Nevertheless, successes have been glaring and unique too. The plant breeders of the Institute concerted attempts were made for the genetic restructuring of the plant-frame in Hyoscyamus niger L. (black henbane) and Cymbopogon martinii (palmarosa), enhanced alkaloid biosynthesis in henbane, weak, or lack of latex biosynthesis in Papaver somniferum L. (Opium poppy), increased productivity of seeds in Plantago ovata F. (isabgol), and new/increased formation of essential oils in Chamomila recutita [L.] Rauschert (Chamomile) and Cymbopogon winterianus (Java citronella). Several qualitative macro mutations were generated for commercial exploitation, e.g. an unbranched (Ub) and physiologically most efficient variety Aekla and high tropane alkaloid bearing variety Aela of H. niger, opium less oil-seed variety Sujata of opium poppy, a dwarf mutant and a male sterile (ms) line of palmarosa, and new compound yielding variety of chamomile and geranium. CONCLUSIONS: The ample quantitative variation was also created by reshuffling the polygenic background in both seed and vegetatively propagated MACs, and subsequently, with applying mutation breeding approach superior varieties were evolved and released after a rigorous screening in the field-evaluation or under pipeline for release. These varieties are Niharika and Mayuri of psyllium; Vallary, CIMAP Sammohak, CIM Ujjwala, and YEL (yellow) of German chamomile and Manjari and CIM Jeeva of Java citronella.

AromaDb: A Database of Medicinal and Aromatic Plant's Aroma Molecules With Phytochemistry and Therapeutic Potentials.

In traditional, herbal medicine, and aromatherapy, use of essential oils and their aroma compounds have been known since long, for the management of various human diseases. The essential oil is a mixture of highly complex, naturally occurring volatile aroma compounds synthesized by medicinal and aromatic plants as secondary metabolites. Essential oils widely used in pharmaceutical, cosmetic, sanitary, food industry and agriculture for their antibacterial, antiviral, antifungal, antiparasitic, insecticidal, anticancer, neuroprotective, psychophysiological, and anti-aging activities. Moreover, volatile aroma compounds comprise a chemically diverse class of low molecular weight organic compounds with significant vapor pressure. However, aroma compounds produced by plants, mainly attract pollinators, seed dispersers and provide defense against pests or pathogens. However, in humans, about 300 active olfactory receptor genes are involved to detect thousands of different aroma compounds and modulates expression of different metabolic genes regulating human psychophysiological activity, brain function, pharmacological signaling, and therapeutic potential. Keeping in mind this importance, present database, namely, AromaDb (http://bioinfo.cimap.res.in/aromadb/) covers information of plant varieties/chemotypes, essential oils, chemical constituents, GC-MS profile, yield variations due to agro-morphological parameters, trade data, aroma compounds, fragrance type, and bioactivity details. The database includes 1,321 aroma chemical structures, bioactivities of essential oil/aroma compounds, 357 fragrance type, 166 commercially used plants, and their high yielding 148 varieties/chemotypes. Also includes calculated cheminformatics properties related to identification, physico-chemical properties, pharmacokinetics, toxicological, and ecological information. Also comprises interacted human genes affecting various diseases related cell signaling pathways correlating the use of aromatherapy. This database could be a useful resource to the plant's growers/producers, an aroma/fragrance industrialist, health professionals, and researchers exploring the potential of essential oils and aroma compounds in the development of novel formulations against human diseases.

Genetic variability, associations, and path analysis of chemical and morphological traits in Indian ginseng [Withania somnifera (L.) Dunal] for selection of higher yielding genotypes.

BACKGROUND: The study was carried out to assess the genetic variability present in ashwagandha and to examine the nature of associations of various traits to the root yield of the plant. METHODS: Fifty-three diverse genetic stocks of ashwagandha (Withania somnifera) were evaluated for 14 quantitative characteristics. Analysis of variance, correlation, and path coefficient analysis were performed using the mean data of 2 years. RESULTS: Analysis of variance revealed that the genotypes differed significantly for all characteristics studied. High heritability in conjunction with high genetic advance was observed for fresh root weight, 12 deoxywithastramonolide in roots, and plant height, which indicated that selection could be effective for these traits. Dry root weight has a tight linkage with plant height and fresh root weight. Further, in path coefficient analysis, fresh root weight, total alkaloid (%) in leaves, and 12 deoxywithastramonolide (%) in roots had the highest positive direct effect on dry root weight. CONCLUSION: Therefore, these characteristics can be exploited to improve dry root weight in ashwagandha genotypes and there is also scope for the selection of promising and specific chemotypes (based on the alkaloid content) from the present germplasm.

Morphological, chemical and molecular characterization of Centella asiatica germplasms for commercial cultivation in the Indo-Gangetic plains.

Centella asiatica germplasm collected from north, north-eastern and southern parts of India was compared for biomass and centellosides productivity under uniform agro-climatic conditions of the Indo-Gangetic plains at Lucknow. The highest biomass accumulation (411.9 g FW/m2 area) was recorded in accession A from north India, followed by 284.0, 135.7 and 29.2 g FW/m2 in accessions M, B and E from southern, eastern and north-eastern regions, respectively. Accession M possessed the highest asiaticoside content (52.1 mg/gDW) that was 1.58, 2.34 and 21.7 folds more than accessions A, B and E, respectively. The madecassoside level in leaves of accessions B and M was comparable (28.9 and 25.7 mg/gDW) and two folds more than accession A (13.9 mg/gDW). The madecassic and asiatic acid content in leaf tissue of all four accessions remained low in Lucknow. Amplified fragment length polymorphism (AFLP) analysis with 23 primers yielded 696 fragments, 563 of which were polymorphic. Accession M out-grouped with genetic dissimilarity indices of 83, 85 and 95% from accessions A, E and B, respectively. Commercial cultivation of accessions M and A through a four months growth cycle (June to September) in agro-climatic conditions of the Indo-Gangetic plains is suggested.

Latex-less opium poppy: cause for less latex and reduced peduncle strength.

A genotype 'Sujata' developed earlier at CSIR-CIMAP from its parent 'Sampada' is considered to be the latex-less variety of Papaver somniferum. These two genotypes are contrasting in terms of latex and stem strength. Earlier we have carried out microarray analysis to identify differentially expressing genes from the capsules of the two genotypes. In this study, the peduncles of the two genotypes were compared for the anatomy revealing less number of laticifers in the cortex and vascular bundles. One of the important cell wall-related genes (for laccase) from the microarray analysis showing significantly higher expression in 'Sampada' capsule was taken up for further characterization in the peduncle here. It was functionally characterized through transient overexpression and RNAi suppression in 'Sujata' and 'Sampada'. The increase in acid insoluble lignin and total lignin in overexpressed tissue of 'Sujata', and comparable decrease in suppressed tissue of 'Sampada', along with corresponding increase and decrease in the transcript abundance of laccase confirm the involvement of laccase in lignin biosynthesis. Negligible transcript in phloem compared to the xylem tissue localized its expression in xylem tissue. This demonstrates the involvement of P. somniferum laccase in lignin biosynthesis of xylem, providing strength to the peduncle/stem and preventing lodging.

Comparative analysis of Papaver somniferum genotypes having contrasting latex and alkaloid profiles.

Papaver somniferum produces therapeutically useful benzylisoquinoline alkaloids (BIAs) like papaverine, thebaine, codeine, and morphine that accumulate in its capsular latex. Morphine is a potent analgesic but is also abused as a narcotic, which has increased the demand for non-narcotic thebaine that can be converted into various analgesics. To curtail the narcotic menace, many distinct genotypes of the plant have been developed that are deficient in morphine and/or latex. Sujata is one such latex-less low alkaloid-producing variety developed from the alkaloid-rich gum harvest variety Sampada. Its utility for gene prospecting and studying differential gene regulation responsible for its low alkaloid, nutritive seed oil, and latex-less phenotype has been exploited in this study. BIA profiling of Sujata and Sampada capsules at the early and late stages indicated that except for thebaine, Sujata had a depressed alkaloid phenotype as compared to Sampada. Comparative transcript-based analysis of the two genotypes was carried out in the early stage capsule (higher thebaine) using subtractive hybridization and microarray. Interrogation of a P. somniferum array yielded many differentially expressing transcripts. Their homology-based annotation classified them into categories--latex related, oil/lipid related, alkaloid related, cell wall related, and others. These leads will be useful to characterize the highly sought after Sujata phenotype.

Growth and asiaticoside production in multiple shoot cultures of a medicinal herb, Centella asiatica (L.) Urban, under the influence of nutrient manipulations.

Growth and in vitro asiaticoside accumulation in multiple shoot cultures of Centella asiatica (L.) Urban was studied as a function of nutrient manipulations in the culture media. Shoot cultures raised in liquid Murashige and Skoog medium supplemented with 2.5 mg/l kinetin attained a growth index (GI) of 6.06 along with the highest asiaticoside content of 3.8 mg/g dry weight on the 35th day of the culture cycle. The shoot growth and asiaticoside accumulation were found to be influenced by the relative proportions of NH(4)(+)-N:NO(3)(-)-N or Cu(2+) concentration in the medium. Asiaticoside content in shoots increased from 5.3 to 8.9 and 8.7 mg/g dry weight when total nitrogen concentration of 60 mM in the control medium was reduced to 50 and 40 mM with a corresponding change in NH(4) (+):NO(3)(-) ratio from 20:40 to 20:30 or 20:20, respectively. Total nitrogen level higher than 60 mM drastically reduced the asiaticoside concentration in these in vitro shoot cultures. Medium devoid of Cu(2+) significantly favored higher asiaticoside accumulation in the cultured tissue (7.05 mg/g dry weight) along with an improved biomass production (GI = 7.7) when compared with shoots reared on the control medium with 0.10 µM Cu(2+) (GI = 5.8; asiaticoside content = 4.4 mg/g dry weight). Carbohydrate enrichment of the medium by increasing the sucrose concentration from 3.0 to 5.0 or 7.0% was also beneficial for biomass and asiaticoside production with GI = 17.1 and 16.9 and asiaticoside content = 7.2 and 5.2 mg/g dry weight, respectively, in comparison to control cultures maintained on medium containing 3.0% sucrose. The procedure described here provides a viable production platform for generating clean and quality material from Centella with high bioactive content.

Growth kinetics and ginsenosides production in transformed hairy roots of American ginseng--Panax quinquefolium L.

A thin, profusely branched, fast growing hairy root line of Panax quinquefolium (American ginseng) was established by co-culturing epicotyl explants with a wild type strain of Agrobacterium rhizogenes. The transformed roots grew by over 10-fold from the initial inoculum within 8 weeks. The crude ginsenosides content in the roots was about 0.2 g/g dry wt level up to the 10th week of culture. Ginsenosides Rb2, Rd, Re, Rf and Rg1 constituted 47-49% of the crude saponin fraction between 6 and 8 weeks of growth whereas, Rc ginsenoside was accumulated only after 9th weeks when the biomass started receding. PCR amplification analysis of the hairy roots confirmed their transgenic nature by showing the presence of Ri-TL DNA with rolA, rolB and rolC genes in their genome.